ORANGE COUNTY, Calif., Feb. 1, 2021 /PRNewswire/ — A recent clinical study published by medical researchers from UC San Diego School of Medicine has established that an expired breath sampling method is comparable to the long-established blood-based method (ABG) of measuring pulmonary gas exchange efficiency.
Published in the American Journal of Physiology Lung Cellular and Molecular Physiology, the study, entitled “Measuring the Efficiency of Pulmonary Gas Exchange Using Expired Gas Instead of Arterial Blood: Comparing the “Ideal” PO2 of Riley with End-Tidal PO2,” demonstrates the reliability and validity of a non-invasive breath-based method of determining A-a gradient (Oxygen Deficit), a standard in respiratory medicine to determine gas exchange efficiency, and previously only available through an invasive arterial blood sampling method.
Using the MediPines AGM100®, a respiratory medical device, researchers were able to demonstrate that the new breath-based measurement of gas exchange efficiency has very low variability and is highly correlated with established blood-sampling methods.
In the new non-invasive method of measuring gas exchange efficiency, concerns of variability in expired breath samples have been addressed. The variability of gas concentrations throughout the respiratory cycle can range dramatically; however, when steady state end-tidal gas samples are used, gas concentration is remarkably constant. The current study found the very low variability of end tidal gas measurements within subjects of 1.3% or 1.4 mmHg for oxygen and 1.8% or 0.7 mmHg for carbon dioxide. The traditional method (Riley Method) does not directly measure the lung alveolar gas level but estimates the alveolar level from a calculation that uses arterial blood gas values and a number of assumptions.
In the age of respiratory diseases like Covid-19, where stability and repeatability of patient measurements matter, this study’s conclusion is a breakthrough finding for quicker, non-invasive methods that are ideally suited for the hospital. A breath-based gas exchange analysis using the AGM100® is easy to obtain for both practitioner and patient. The gas exchange analysis provided by the AGM100® requires the patient to simply breath into a mouthpiece and can be completed within two minutes.
“This study demonstrates the merits of a breath-sampling based approach, given the low variability, which allows for high reproducibility and reliability in clinical practice. This is consistent with our previous study that demonstrated a very high correlation and low measurement bias of directly measured arterial PO2, with that estimated non-invasively from the AGM100 in a range of different physiological states,” said Dr. Phil Ainslie, Canada Research Chair and Co-Director of the Centre for Heart lung and Vascular Health, School of Health and Exercise Sciences at the University of British Columbia.
This finding further supports a clinical validation study published in 2020 by researchers from the University of British Columbia and Duke University Medical Center, demonstrating the high precision of the new expired breath sampling method.
MediPines AGM100® is the world’s first non-invasive gas exchange analyzer. This advanced respiratory monitoring system was designed to rapidly detect respiratory impairment caused by conditions such as COVID-19, chronic obstructive pulmonary disease (COPD), pneumonia, ARDS, pulmonary edema, and pulmonary embolism. The device is FDA cleared and approved for Health Canada COVID-19 Emergency Use. It provides a comprehensive panel of respiratory measurements including blood oxygen levels, Oxygen Deficit (A-a gradient), P/F ratio, and alveolar oxygen and carbon dioxide levels.
MediPines Corporation, based in California, is a market leader in respiratory assessment and monitoring of pulmonary gas exchange. The company mission is to advance respiratory medicine by providing physiology-based respiratory devices that enhance clinical effectiveness and achieve better patient outcomes.